1. Field of the Invention
The present invention relates generally to an optical storage device, and more particularly to a cartridge loading mechanism for an optical storage device.
2. Description of the Related Art
An optical disk has received attention as a memory medium that becomes a core in the recent rapid development of multimedia, and it is usually accommodated in a cartridge case to be provided as an optical disk cartridge for practical use. The optical disk cartridge is loaded into an optical disk drive to perform reading/writing of data (information) from/to the optical disk by means of an optical pickup (optical head).
A recent optical disk drive intended to realize size reduction is composed of a fixed optical assembly including a laser diode module, a polarization beam splitter for reflecting and transmitting a laser beam, and a photodetector for receiving reflected light from an optical disk, and a movable optical assembly including a carriage and an optical head having an objective lens and a beam raising mirror mounted on the carriage. The carriage is movable in the radial direction of the optical disk along a pair of rails by means of a voice coil motor.
A write-power laser beam emitted from the laser diode module of the fixed optical assembly is first collimated by a collimator lens, next transmitted by the polarization beam splitter, then reflected by the beam raising mirror of the optical head, and finally focused on the optical disk by the objective lens, thereby writing data onto the optical disk. On the other hand, data reading is performed by directing a read-power laser beam onto the optical disk. Reflected light from the optical disk is first collimated by the objective lens, next reflected by the polarization beam splitter of the fixed optical assembly, and finally detected by the photodetector, thereby converting the detected optical signal into an electrical signal.
A conventional cartridge loading mechanism is operated in the following manner. When an optical disk cartridge is inserted into an optical disk drive, a slide plate is pushed to be moved toward the rear end of the optical disk drive by the cartridge. The slide plate is connected through a link mechanism to a spindle motor. When the slide plate is moved as mentioned above, the spindle motor is accordingly raised to chuck a hub of the optical disk, thereby holding the optical disk on the spindle motor. When the spindle motor is operated to rotate the optical disk at a high speed, the optical head is operated to read/write data from/to the optical disk.
However, the conventional cartridge loading mechanism is not provided with a stopper for preventing movement of the spindle motor in its loading direction in the condition that the optical disk cartridge is not inserted in the optical disk drive. Accordingly, when an external shock or the like is applied to the conventional optical disk drive in which the optical disk cartridge is not inserted, there is a possibility that the spindle motor may be moved in the loading direction. When the spindle motor is moved in the loading direction, there arises a problem that the optical disk cartridge may interfere with the spindle motor during insertion of the optical disk cartridge into the optical disk drive.
It is therefore an object of the present invention to provide an optical storage device which can prevent the movement of the spindle motor in the loading direction when the optical disk cartridge is not inserted in the optical storage device.
In accordance with an aspect of the present invention, there is provided an optical storage device capable of at least reading information recorded on an optical recording medium, comprising: a base; a light source mounted on the base; an optical head having an objective lens for focusing light from the light source onto the optical recording medium; a photodetector mounted on the base for detecting a regenerative signal from reflected light from the optical recording medium; a spindle motor; a spindle motor assembly having the spindle motor and movable between a raised position where the spindle motor engages with the optical recording medium inserted in the optical storage device and a lowered position where the spindle motor disengages the optical recording medium; a link mechanism for moving the spindle motor assembly between the raised position and the lowered position according to insertion and ejection of the optical recording medium with respect to the optical storage device; and a stopper for engaging the link mechanism to prevent movement of the link mechanism when the optical recording medium is not inserted in the optical storage device, thereby preventing movement of the spindle motor assembly to the raised position.
Preferably, the optical storage device further comprises a carriage on which the optical head is mounted, the carriage being movable in a radial direction of the optical recording medium inserted in the optical storage device; and a carriage lock lever for locking the carriage when the optical recording medium is not inserted in the optical storage device. More preferably, the stopper is formed integrally with the carriage lock lever, and when the optical recording medium is inserted into the optical storage device, the carriage lock lever and the stopper are simultaneously released.
More preferably, the optical recording medium is accommodated in a cartridge case and provided as a cartridge; and the link mechanism comprises a slide plate movable between a first position where the cartridge is not inserted in the optical storage device and a second position where the slide plate is pushed to be moved by the cartridge inserted into the optical storage device, and a load plate operatively connected to the slide plate and movable between a third position where the spindle motor assembly is in the lowered position and a fourth position where the spindle motor assembly is in the raised position. More preferably, the load plate has a plurality of lift guides for moving the spindle motor assembly to the raised position according to movement of the load plate from the third position to the fourth position.
In accordance with another aspect of the present invention, there is provided a cartridge loading mechanism in an optical storage device for loading a cartridge including a cartridge case and an optical recording medium accommodated in the cartridge case, comprising: a base; a slide plate movable between a first position where the cartridge is not inserted in the optical storage device and a second position where the slide plate is pushed to be moved by the cartridge inserted into the optical storage device; a spindle motor assembly having a spindle motor and movable between a raised position where the spindle motor engages the optical recording medium of the cartridge inserted in the optical storage device and a lowered position where the spindle motor disengages the optical recording medium; a load plate operatively connected to the slide plate and movable between a third position where the spindle motor assembly is in the lowered position and a fourth position where the spindle motor assembly is in the raised position; and means for locking the load plate at the third position.
The above and other objects, features and advantages of the present invention and the manner of realizing them will become more apparent, and the invention itself will best be understood from a study of the following description and appended claims with reference to the attached drawings showing some preferred embodiments of the invention.